1. 4EH7 - This is a dual-triode preamp tube with a 12AX7-style pinout. It has a maximum plate voltage rating of 250 volts and a maximum plate current rating of 20 mA. It features an internal shield between its two triode sections to reduce hum and noise. Its gain is relatively low, making it a good choice for use in low-gain preamps and line level amplifiers.
2. Features - This tube is designed to provide low-noise performance, minimal distortion and low microphonics. It consists of two triode sections, each having its own 12AX7-style pinout. The 4EH7 is an indirectly heated tube meaning that an indirect heater voltage is supplied to the cathode elements indirectly, contributing to low noise and consistent performance.
3. Applications - This dual-triode is often used as a line-level preamp tube, as well as for low-gain amplifiers. It can also be used for gain stages for electric guitars and bass guitars.
4. Characteristics - The 4EH7 exhibits a relatively low gain and can handle up to 250 volts on the plate. It has a maximum plate current rating of 20 mA and features a low noise level and excellent power efficiency.